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544 Uppsatser om Wood boring insects - Sida 3 av 37
Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser
Most of the saw and pulp industries have stored wood nearby their production, the main
reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality.
One drawback of wet storage of wood is the leaching of chemical substances into the
surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and
organic substances. These substances can cause problems for the surrounding environment.
The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.
Teknisk och ekonomisk analys av en bränslekonvertering vid SIA TallOils pelletsfabrik :
At SIA TallOil's pellets factory in Latvia wood shavings and saw dust are dried with flue gases from a gas burner. TallOil wants to replace the gas with a biofuel that is available at the pellet plant. The reason for this is the unstable gas market in Europe in combination with the fact that TallOil wants to improve its profile as supplier of renewable bio fuels. In this project the technical and economical possibilities for a fuel conversion to ether bark powder, wood shavings or wood powder have been investigated. These fuels should be burned in one of the following applications: TPS BioSwirl, VTS Multifuel burner or Saxlunds bio fuel combustion plant
Due to the fact that the fuel alternatives available are relatively common except for bark powder, the work has mainly been focused on bark powder.
Liv i d?d ved: En unders?kning av f?rh?llningss?tt till d?d ved p? ?ppeltr?d i tr?dg?rdshandb?cker och bland yrkesverksamma tr?dbesk?rare
In this essay, several factors in apple tree care (specifically in relation to whether dead wood
should be kept or removed) are highlighted for example, aesthetics and biodiversity.
To present some background, the essay begins by introducing some previous literature on
dead wood. This leads into how dead wood is treated within forestry. Next, previous research
on dead wood in fruit trees is mentioned. Cultural and historical management methods are
also highlighted.
Död ved i ett referensvattendrag
The purpose with this study is to find out how much dead wood we can expect us to find in a Russian reference river and compare with studies from Swedish streams. Dead wood are an important structure for the biodiversity in forest streams, studies have shown that population of trout can increase with up to 300 % when the amount of dead wood are increasing from 0 to 8 ? 16 LWD (Large woody debris)/100 m2. Dead wood are also an important structure for the stream character, formations of dams and pools which are important habitats and reproduction areas for salmon and brown trout.
The study where taken place in tributaries to the Russian river Varzuga in the North West part of Russia outside Murmansk. Varzuga has low impact of human activity and is considered to be a reference river to rivers in northern Sweden.
Marknadsundersökning för SCA Skog AB avseende utbor i Mälardalen :
The need of raw material does of course fluctuate but the long term view is an increasing demand due to the growing consumption of sawn timber products, pulp, paper and lately also biomass. This has led to a keener competition for wood. At the same time there is an ongoing structural change of a significant part in the Swedish wood supply market, the private forest owners. In 1992,
22 % of Sweden´s 335 000 private forest owner lived apart from their forest. In 2007 this figure had risen to 36 %.
Biologisk mångfald i små grönområden : Inventering av insekter och fåglar i bebyggda områden i Solna kommun
All over the world the urbanisation increases at the expense of green areas. Many plants and animals are endangered today because their habitats gets smaller or disappear. The green areas that are left in city centres and suburbs are often small and surrounded by roads and buildings. Despite this, several studies have shown that these small green areas may house large biological diversity.This project aims to study the biological diversity in small green patches in residential areas. The study has been carried out in Råsunda in Solna municipality (Stockholm county) during the period May?July 2006.Three equivalent areas (5000?10 000 m2) with quite many old oaks were chosen for the study and inventoried for birds and saproxylic insects.
Biologisk mångfald i små grönområden : Inventering av insekter och fåglar i bebyggda områden i Solna kommun
All over the world the urbanisation increases at the expense of green areas. Many plants and animals are endangered today because their habitats gets smaller or disappear. The green areas that are left in city centres and suburbs are often small and surrounded by roads and buildings. Despite this, several studies have shown that these small green areas may house large biological diversity.This project aims to study the biological diversity in small green patches in residential areas. The study has been carried out in Råsunda in Solna municipality (Stockholm county) during the period May?July 2006.Three equivalent areas (5000?10 000 m2) with quite many old oaks were chosen for the study and inventoried for birds and saproxylic insects.
En jämförelse av skogsmarksprisets utveckling mellan Sverige, Danmark, Norge, Finland, Estland och Lettland
During the twenty-first century the price of forest land in Sweden has increased heavily. Buying forest land has become more common and the stakeholders have grown in number.
The countries around Sweden have through the globalization become connected in the market of round wood and wood products. The price of forest land and round wood are also close connected.
The goal with this report is to make a comparison of forest land prices between Sweden, Denmark, Norway, Finland, Estonia and Latvia and to see how the prices have developed in the period 2000-2011. The prime factor in the comparison, except the direct price difference between the countries, is the round wood prices. The round wood prices give information about the economic situation in the countries and play an important role in the return on the forest land.
The prices of forest land shifts heavily between the countries.
Pelletskvalitet : Test av olika råvarumixer i pelletstillverkningen vid Rindi Västerdala AB:s bioenergikombinat i Vansbro
Fuel pellets are a refined bio fuel mostly consisting of residues from sawmills and wood industry. At Rindi Västerdala AB's combined bio energy plant in Vansbro fuel pellets are produced, while the waste heat from the process is used for district heating. The pellets are produced from sawdust, wood shavings and dry wood chips that is dried, milled and pressed into small cylindrical rods. The advantage of refining the wood material in this manner is that the energy value is greater per unit volume and unit weight, thereby the cost of transportation per energy unit is reduced. Also, less storage space is needed.Pellet manufacturing is a complex process since many parameters affects the final results.
ELever möter Lagerlöf : en responsstudie av gymnasieelevers första möte med en text
This study examines the way Swedish students in Upper Secondary School respond to two excerpts from a classic Swedish novel. The paper?s aim is both to give an overview over some of the theoretical concepts concerning the field of reader-response criticism, and to describe and analyse what the students experience in their first meeting with an older text. The background to my interest is the many studies showing that young readers regard reading of fiction in school as boring. By using the method of written reading responses I want to contribute to a deeper understanding of how an older text can be received, understood and engage its readers.
Energy efficient storage of biomass at Vattenfall heat and power plants
Storage of biomass is often associated with problems such as heat development, dry
matter losses and reduction of fuel quality. The rise in temperature can potentially
cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles
can cause health problems in the surrounding. The dry matter losses and reduction of
fuel quality can have economical effects. The aim of this thesis project is to develop
guidelines on how to store large amount of biomass at Vattenfalls heat and power
plants in an optimal way.
Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap
Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).
Identifiering av lek- och övervintringsområden för lax (Salmo salar) och öring (Salmo trutta) i Klarälven
Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).
Hållbara uppvärmningsalternativ för Grinda Wärdshus : En studie om uppvärmning med pellets och flis
This report is a bachelor's thesis of two students from the Energy and Environment degree at KTH Stockholm. Grinda is an island situated Stockholm archipelago. Skärgårdsstiftelsen is landowners and manages the area. Grinda Wärdshus, a guest house located in the island, currently uses an oil-fired boiler as a heating system. The aim of this thesis is to investigate whether wood chips or pellets is, from a sustainability standpoint, a suitable heating method for the guest house.
Molecular analysis of insecticide resistance in pollen beetle (Meligethes aeneus)
The escalating usage of pyrethroids has resulted in an increased awareness about resistance towards pyrethroids in insects. Pyrethroids inhibit voltage-sensitive sodium channels (VSSC) in nerve cell membranes and are composed of synthetic molecules based on pyrethrins present in pyrethrum extracts from Chrysanthemum species. VSSC are transmembrane proteins that are important for electric signalling over the membrane in insects. Mutations in the gene encoding the sodium channel have proved to be a common reason for resistance against pyrethroids. Pyrethroid resistance among pollen beetles is spread all over Sweden and also abroad and is increasing.